The imaging core is build around a state-of-the-art facility, the expertise of the optical and electron microscopy personnel and the experience of each of the subproject investigators in imaging. The central core facility will constitute a focus of interaction for the program, and will provide for consistent imaging performance and interpretation. The facility is equipped for quantitative confocal and 2-photon microscopy (Bio-Rad MRC-1024), digital deconvolution wide-field microscopy (Applied Precision Deltavision deconvolution software) and electron microscopy (Phillips CM120 TEM). It is the objective of the imaging core facility to apply, develop and combined these technologies to provide a rational, integrated approach to three-dimensional microscopic imaging of polarized epithelial cells. The specific mission of the core facility will be to, 1. provide quantitative imaging to support each of the 4 program subprojects, 2. implement digital image deconvolution techniques to support a 4 way strategy of high resolution three-dimensional optical imaging employing confocal microscopy, 2-photon microscopy and image deconvolution of wilde-field and confocal images and, 3. develop methods of three-dimensional imaging of living polarized epithelial cells. With the completion of these aims, the imaging core will have been developed into a unique resource for the study of renal cell biology.